A charger with active protection function includes: a power conversion module group, a monitoring unit and an output module group; wherein the power conversion module group is respectively connected with the monitoring unit and the output module group; the monitoring unit is connected with the output module group; the charger with active protection function is connected with an electric vehicle via the output module group to charge the electric vehicle; and when the charger with active protection function is connected with the electric vehicle, the charger with active protection function communicates with BMS of a vehicle via the output module group. The output module group obtains real-time charging data of the electric battery of the BMS. The output module group combines the warn value and threshold value to judge whether the BMS and the power battery are in abnormal condition during charging process.